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Efficient enzymatic synthesis of d -xylose and l -arabinose lauryl mono- and diesters has been achieved by transesterification reactions catalysed by immobilized Candida antarctica lipase B as biocatalyst, in organic medium in the presence of d -xylose or l -arabinose and vinyllaurate at 50 °C. In case of l -arabinose, one monoester and one diester were obtained in a 57% overall yield. A more complex mixture was produced for d -xylose as two monoesters and two diesters were synthesized in a 74.9% global yield. The structures of all these pentose laurate esters was solved. Results demonstrated that the esterification first occurred regioselectively onto the primary hydroxyl groups. Pentose laurate esters exhibited interesting features such as low critical aggregation concentrations values all inferior to 25 μM. Our study demonstrates that the enzymatic production of l -arabinose and d -xylose-based esters represents an interesting approach for the production of green surfactants from lignocellulosic biomass-derived pentoses. [ABSTRACT FROM AUTHOR]

A series of new “green” ionic liquids was prepared in two or three steps from natural and low expense Glycine Betaine (GB). Esterification of GB was carried out with methanesulfonic acid and primary alcohols with alkyl chains containing 6, 12, 14, 16 and 22 atoms of carbon. Anionic metathesis from these cationic esters with inorganic (ClO 4 − , BF 4 − ) or biobased (( S )-CH 3 -CHOH-COO − (Lac − )) anions was then achieved to afford a range of fully characterized ionic liquids. The influence of the alkyl chain length and the chemical nature of the counter anion on physicochemical properties such as melting point, glass transition, decomposition temperatures and viscosity has been investigated. [ABSTRACT FROM AUTHOR]

Highlights: [•] Mutations of aromatic residues in the aglycone binding subsite of a β-xylosidase modify its hydrolytic and transglycosylation activities. [•] F116, F167 and Y284 play an important role in hydrolysis of pNP β-d-Xylp. [•] F116 represents an interesting target to enhance the transglycosylation reaction with octanol. [ABSTRACT FROM AUTHOR]

A diagram is presented which explains the chemical process of Perfluoroalkylation of Nitrones for the Synthesis of a Series of Fucosidase Inhibitors.